Police blocked routes in and out of Pochayiv
in western Ukraine and the monastery, which is inside the town but surrounded
by an ancient wall, was closed to the public.

Pochayiv Lavra (monastery) belongs to the
Ukrainian branch of the Russian Orthodox Church. Hundreds of thousands of pilgrims
visit every year from Poland, Moldova, Russia, Belarus and as far away as
Bulgaria.

The town of Pochayiv has a population of 8,000
people and it is thought that priests will have had contact with many of the
residents.